Cool you are testing, you actually shouldn’t have to run the Launcher and Demo_app at all. It’s just uploading (all data gets encrypted and chunked and spread over the network). So whenever someone requests your site it comes out of the network even if you are offline for several days.
About the data missing, what I’ve learned is that the network was under attack. Normally one should pay some Safecoin to create an account or to store some data. Without Safecoin one could quite easily attack the network. They can’t get it offline but they can, for example try to start 50 Vaults and take them all offline at once etc. Here’s more info from David Irvine:
So we’ll have a weekly update tonight and hopefully learn more. Great you are testing anyway. I’m running a Vault now and then.